The article analyses all documented coin finds from the fortifications in the Claustra Alpium Iuliarum defence system. The author interprets fluctuations in the intensity of monetary ...circulation that would reflect life or activity at individual forts. Coin finds are also presented from archaeological contexts that can definitely be connected to building activities on walled defensive structures. Data are presented about the latest coins from individual for-tifications, which indicate an interruption in the regular influx of money into circulation and thus also a break in the intensity of life at the fortifications. In this manner, it is established that the first construction activities in building the fort of Castra can be placed as early as the 280s, while otherwise rare coin finds in the towers of the defence system indicate building activities no earlier than the mid 4th century. Coin finds show an interruption in monetary circulation at the Lanišče and Martinj hrib forts at the end of the 380s, at Tarsatica at the end of the 4thcentury, while coins also from the beginning of the 5thcentury were found at the forts of Castra and Ad Pirum.
According to the author Livy (Ab Urbe condita, XXXIX, 22, 45, 54–55) in 186 BC a large amount of Gauls crossed the Alps to found an oppidum, not far from the place where Aquileia would be located. ...Three years later, a resolute Roman intervention forced these migrants to return to their homeland. This research, evaluating the contributions of previous bibliography, seeks to identify the name of the Transalpine Gauls in the Taurisci. In addition, based primarily on historical and topographical considerations, we come to the following hypothesis: the route chosen to cross the Alps may have been the one through the passage that, in a later period, would be called Ad Pirum by the Romans.
